List of Portals used in Azure World
https://portal.azure.com
https://preview.portal.azure.com
https://aad.portal.azure.com
Microsoft 365 Device Management
https://devicemanagement.portal.azure.com
https://ea.azure.com
https://www.microsoftazuresponsorships.com
https://account.azure.com/Subscriptions
List of Azure DevOps Organisations
https://aex.dev.azure.com
Formerly https://app.vssps.visualstudio.com
https://resources.azure.com/
https://shell.azure.com
https://manage.windowsazure.com
Multi-factor Authentication
https://account.activedirectory.windowsazure.com/usermanagement/multifactorverification.aspx
Main Landing Page (Not admin)
https://portal.office.com
Now redirects to https://www.office.com
https://admin.microsoft.com
https://portal.office.com/commerce/manage.aspx?empty=1
https://myapps.microsoft.com/
Redirects to https://account.activedirectory.windowsazure.com/r#/applications
Other useful Microsoft Links
Visual Studio Subscriptions Administration
https://manage.visualstudio.com
My Visual Studio & MSDN Benefits
https://my.visualstudio.com
Microsoft Next Gen Volume Licensing
https://businessaccount.microsoft.com
https://msdn.microsoft.com